Mobile Ad-hoc Network (MANET) is a dynamic network topology in which nodes move without restraint anytime and anywhere; it does not require centralized authorization. Previous researches used traditional cryptographic or authentication function for security. Recently many trust-based routing protocols have been introduced but each has its own limitations. In MANETs, trust is a challenging task. In this network, it is imperative for the nodes to work in a trusted and cooperative way. This paper proposed a new secure trust based routing scheme which is combination of social and QoS trust. The primary goal of our proposed scheme is to mitigate nodes performing various packet forwarding misbehaviors. We calculated four parameters for trust which are control forward ratio, data forward ratio, intimacy and residual energy. We present adversary model of the packet dropping attack against which our trust-based scheme is evaluated. Simulation results in NS-2 show that the proposed scheme improves performance in terms of packet delivery ratio (PDR).